acta ethologica

, 12:87

Age-related migration patterns in Larus fuscus spp.

  • Paulo A. M. Marques
  • Ana M. Costa
  • Peter Rock
  • Paulo E. Jorge
Original Paper

DOI: 10.1007/s10211-009-0060-y

Cite this article as:
Marques, P.A.M., Costa, A.M., Rock, P. et al. acta ethol (2009) 12: 87. doi:10.1007/s10211-009-0060-y

Abstract

Migration is a critical period in a bird’s life that can affect the fitness of individuals. Intra-population migratory patterns and the way different sex and/or age classes within a population differ in timing and/or distance of migration are not completely understood. The present study aims to observe inter- and intra-population migratory patterns in the western population of Lesser Black-backed Gulls (Larus fuscus spp.), shedding light on age-related differences of temporal patterns of occurrence in the Portuguese coastal areas during migration and winter. One thousand seven hundred and fifty-four colour ring records were analysed matching a 30-year period of observations on the Portuguese coast between 1975 and 2005. During migration, the graellsii population represents 90% of the migratory flow of L. fuscus through Portugal with the intermedius accounting for 9% and the fuscus population, being vestigial in this period, accounting for 1%. Nevertheless, interesting significant differences were observed between the age classes of the three populations during this period, the graellsii population having a large number of first winters (40% of the migratory contingent of this population) followed by immatures and adults whilst in the intermedius and fuscus populations, the largest age class is the adults. During winter, no inter-population differences were found. When comparing migration and winter periods, intra-population differences were found in the graellsii and fuscus populations regarding distribution and age classes. These results indicate different migratory routes amongst different populations suggesting a leapfrog migration in L. fuscus and also a differential age-related migration pattern that might result from first winters migrating further south in search of a wintering place since adults heavily occupy the closest wintering quarters in their attempt to arrive earlier at their breeding ground.

Keywords

MigrationWintering quartersBreeding areasMigratory patternsWestern Lesser Black-backed Gulls

Copyright information

© Springer-Verlag and ISPA 2009

Authors and Affiliations

  • Paulo A. M. Marques
    • 1
    • 2
  • Ana M. Costa
    • 3
  • Peter Rock
    • 4
  • Paulo E. Jorge
    • 1
  1. 1.Centro de Biologia Ambiental, Museu Nacional de História NaturalUniversidade de LisboaLisboaPortugal
  2. 2.Departamento de Biodiversidad y Biología EvolutivaMuseo Nacional de Ciencias Naturales (CSIC)MadridSpain
  3. 3.Faculdade de CiênciasUniversidade de LisboaLisboaPortugal
  4. 4.BristolUK